JP5794841B2 - Fastening structure - Google Patents

Description

  The present invention relates to a fastening structure in which a plurality of members to be fastened are fastened using bolts with holes (for example, hexagonal holes).

  Generally, a fastening structure using a bolt with a hole forms a female screw part into which a male screw part of a bolt is screwed into one fastened member, and a through-hole through which the male screw part of the bolt is inserted into the other fastened member. A recess (so-called counterbore hole) that accommodates the head of the bolt that is continuous is formed, and the bolt is screwed into the female screw portion and tightened through the recess and the through hole. In this fastening structure, various reverse detent structures have been proposed in the past in order to prevent the bolt with a hole from naturally turning and loosening in the direction opposite to that of tightening. Among them, some have been proposed that use a bolt head and a recess for receiving the bolt head.

  For example, in Patent Document 1, a vertical groove is formed on the head of the bolt and the side of the recess, and a detent ring is inserted between the side of the head of the bolt and the inner surface of the recess. A fastening structure is described in which a pin is inserted into a groove and a part of a side surface of a detent ring is pressed and caulked to integrally fix a bolt head, a detent ring, and a recess. . Further, in Patent Document 2, a wing-like protruding piece that protrudes outward from a part of the outer periphery and is elastically deformable is formed on the head of the bolt, and the bolt is about to turn in the opposite direction on the side surface of the recess. There is described a fastening structure in which a stopper projection for preventing rotation of a bolt is formed by abutment of a tip of a blade-like projecting piece.

Japanese Utility Model Publication No. 02-040111 WO2009 / 001421 publication

  However, the fastening structures of Patent Document 1 and Patent Document 2 have a complicated structure and are likely to increase costs. That is, in the fastening structures of Patent Literature 1 and Patent Literature 2, it is necessary to form a recess formed in the fastened member in a special shape. Moreover, the fastening structure of Patent Document 1 requires two types of members for preventing loosening (a rotation prevention ring and a pin member), and also requires work after tightening and fastening. The fastening structure of Patent Document 2 has a very complicated structure in which an elastically deformable blade-shaped projecting piece is formed on the head of a bolt.

  This invention is made | formed in view of the reason which concerns, The objective is to provide the fastening structure which implement | achieves a reverse rotation prevention structure, without making a structure complicated.

In order to achieve the above object, a fastening structure according to claim 1 is provided with one member to be fastened in which a female screw portion is formed, and the other in which a through hole and a recess having a predetermined inner diameter are formed. A bolt with a hole in which a neck portion whose outer diameter is gradually increased from the male screw portion side to the head side is formed between the fastened member of the male screw portion and the head screwed to the female screw portion; An annular reverse detent ring having a predetermined outer diameter having a central hole through which a part of the neck of the bolt is inserted, and a slit leading to the central hole is formed. By screwing and tightening the male threaded portion of the bolt to the female threaded portion through the hole, both the fastened members are fastened, and by tightening, the reverse rotation prevention ring is expanded, and the outer wall surface thereof is recessed. in contact with the inner wall surface of the place Ri, the reverse detent ring is characterized in that it has a narrow portion in the opposing portions of the slit.

The fastening structure according to claim 2 includes: one fastening member formed with a female screw portion; the other fastening member formed with a through hole and a recess having a predetermined inner diameter continuous thereto; and the female screw A bolt with a hole in which a neck portion whose outer diameter gradually increases from the male screw portion side to the head side is formed between the male screw portion and the head screwed to the head portion, and a part of the neck portion of the bolt is An annular reverse detent ring having a predetermined outer diameter having a central hole to be inserted and having a slit leading to the central hole, and the male threaded portion of the bolt is passed through the recess and the through hole. Both the fastened members are fastened by being screwed into the female screw portion and tightened, and by tightening, the reverse rotation prevention ring is expanded and its outer wall surface comes into contact with the inner wall surface of the recess. The reverse rotation prevention ring Half-ring portion is defined by a line passing through the definitive center and the slit, characterized in that the width in the radial direction are different from each other.

  According to the fastening structure of the present invention, the reverse rotation prevention structure is realized without complicating the structure by the bolt formed with the neck and the reverse rotation prevention ring. It is not necessary to make the recess formed in a special shape, and it is possible to prevent reverse rotation only by tightening.

It is sectional drawing of the fastening structure which concerns on embodiment of this invention, (a) is the state in the middle of fastening work, (b) is the state at the time of completion of fastening work. The bolt used for the fastening structure same as the above is shown, (a) is a plan view, (b) is a side view, and (c) is a bottom view. The reverse rotation prevention ring used for a fastening structure same as the above is shown, (a) is a plan view, (b) is a side view, and (c) is a bottom view. The modification of the reverse rotation prevention ring used for a fastening structure same as the above is shown, (a) is a top view, (b) is sectional drawing.

  Hereinafter, preferred embodiments for carrying out the present invention will be described with reference to the drawings. As shown in FIG. 1, a fastening structure 1 according to an embodiment of the present invention fastens one fastened member 4 and the other fastened member 5 using a bolt 2 with a hole and a reverse rotation prevention ring 3. It is a thing.

  The bolt 2 with a hole has the head 21 and the external thread part 22, as shown in FIG. 2, similarly to the bolt with a normal hole. The head 21 has a tool hole (for example, a hexagonal hole) 21a formed near the center of the zenith. The male screw portion 22 is formed with a thread that is screwed into the female screw portion 41 of one of the fastened members 4. The bolt 2 can be rotated by inserting and turning a tool (for example, a hexagonal wrench) in the tool hole 21a.

  The bolt 2 has a neck portion 23 formed between the male screw portion 22 and the head portion 21. This neck portion 23 is a characteristic part of the bolt 2. The side surface of the neck portion 23 is inclined so that the outer diameter gradually increases from the male screw portion 22 side to the head portion 21 side. More specifically, the neck portion 23 may be configured such that the side surface is inclined in an axisymmetric shape in a truncated cone shape.

  As shown in FIG. 3, the reverse rotation prevention ring 3 has an annular shape having a predetermined outer diameter, and has a central hole 3 a through which a part of the neck portion 23 of the bolt 2 is inserted, and the central hole 3 a A slit 3b is formed. The center hole 3a has an inner diameter larger than a minimum diameter portion of the neck portion 23 of the bolt 2 and smaller than a maximum diameter portion of the neck portion 23 in a normal state.

  Moreover, when the reverse rotation prevention ring 3 is arrange | positioned around the neck part 23 of the volt | bolt 2, it is preferable that the internal diameter of the center hole 3a becomes large gradually as it becomes the head 21 side of the thickness direction. More specifically, it is preferable that the inner wall surface 3aa of the central hole 3a is inclined axially symmetrically at substantially the same inclination angle as the side surface of the neck 23 of the bolt 2. This makes it easier for the reverse rotation prevention ring 3 to come into contact with the bolt 2 at an appropriate position (that is, without tilting relatively), and as a result, the reverse rotation prevention ring 3 is connected to the neck 23 of the bolt 2 as will be described later. When it is spread by, it becomes easy to be spread stably.

  Further, it is preferable that the portion of the reverse rotation prevention ring 3 that faces the slit 3b has a narrow portion 3cb by providing a notch 3ca so that both sides thereof can be easily spread.

  Further, in the process of forming the male threaded portion 22 of the bolt 2, if the reverse rotation prevention ring 3 is disposed around the neck portion 23 and then the threaded machining of the male threaded portion 22 of the bolt 2 is performed, then the thread rises. Therefore, it is possible to prevent the reverse rotation prevention ring 3 from being detached from the bolt 2. If it carries out like this, it is easy to handle in the process in which the volt | bolt 2 and the reverse rotation prevention ring 3 distribute | circulate, and it is quick and can make mistakes (error of the direction of the reverse rotation prevention ring 3 etc.) quickly in fastening operation | work.

  One and the other fastened members 4 and 5 to be fastened by using the bolt 2 and the reverse rotation prevention ring 3 are processed in the same manner as the fastened members to be fastened by using a bolt with a normal hole. ing. That is, a female screw portion 41 that is screwed with the male screw portion 22 of the bolt 2 is formed in one of the fastened members 4. The other fastened member 5 has a through hole 51 and a recess (so-called counterbore hole) 52 formed continuously therewith. Here, the inner diameter of the recess 52 is such that the neck 23 of the bolt 2, the reverse rotation prevention ring 3, and the recess 52 have a predetermined relationship before and after the tightening operation in the fastening operation described below. It is decided.

  The fastening operation is performed as follows. First, the positions of one of the fastened members 4 and the other of the fastened members 5 are aligned, and the male screw portion 22 of the bolt 2 with the reverse rotation prevention ring 3 attached around the neck portion 23 is passed through the recess 52 and the through hole 51. The bolt 41 is screwed into the portion 41 (see FIG. 1A), and the bolt 2 is tightened using the above tool. Here, when tightened to some extent, the reverse rotation prevention ring 3 comes into contact with the bottom 52a of the recess 52, and the reverse rotation prevention ring 3 moves around the neck portion 23 of the bolt 2 from the male screw portion 22 side to the head 21 side. Be made. When further tightened, the outer diameter of the head portion 21 side of the neck portion 23 is gradually larger than that of the male screw portion 22 side, so that the inner wall surface 3aa of the central hole 3a of the reverse rotation prevention ring 3 contacts the neck portion 23. While being pushed out. When the fastening operation is completed, the outer wall surface 3d of the reverse rotation prevention ring 3 comes into contact with the inner wall surface 52b of the recess 52 so as to be pressed.

  Thus, the fastening structure 1 after the tightening operation is completed is such that the reverse rotation prevention ring 3 is sandwiched between the bolt 2 and the inner wall surface 52b of the recess 52, so that the friction between the reverse rotation prevention ring 3 and the bolt 2 is achieved. It is possible to prevent the bolt 2 from being loosened by turning in the reverse direction of tightening due to the force and the frictional force of the reverse rotation prevention ring 3 and the recess 52. As described above, the fastening structure 1 realizes the reverse rotation prevention structure without complicating the structure by the bolt 2 formed with the neck portion 23 and the reverse rotation prevention ring 3, and as a result, the number of members is small. However, the recess 52 formed in the other fastened member 5 does not need to have a special shape, and the reverse rotation can be prevented only by tightening.

  Further, the reverse rotation prevention ring 3 includes half ring portions 3ea and 3eb on both sides of the slit 3b, that is, half ring portions 3ea defined by a line passing through the center of the center hole 3a and the slit 3b, as shown in FIG. 3eb is not symmetrical and may have different radial widths. In this manner, in the tightening process, the bolt 2 is pushed from the wider side, and the axial direction of the bolt 2 is slightly inclined from the axial direction of the female thread portion 41 of the one fastened member 4. As a result, a portion that makes contact with a part of the male screw portion 22 and the female screw portion 41 of the bolt 2 with a strong force can be formed, so that it is possible to make it more difficult to prevent loosening.

  The fastening member according to the embodiment of the present invention has been described above, but the present invention is not limited to that described in the embodiment, and various design changes within the scope of the matters described in the claims. Is possible. For example, although the hexagonal hole is shown as the tool hole in the above figure, it may have another shape such as a cross hole.

DESCRIPTION OF SYMBOLS 1 Fastening structure 2 Bolt 21 Bolt head 22 Bolt male thread part 23 Bolt neck part 3 Reverse rotation prevention ring 3a Center hole of reverse rotation prevention ring 3b Reverse rotation prevention ring slit 3cb Narrow part of reverse rotation prevention ring 3d Outer wall surface of reverse rotation prevention ring 3ea, 3eb Half ring portion of reverse rotation prevention ring 4 One fastened member 41 Female thread portion 5 Other fastened member 51 Through-hole 52 Recess 52b Recess inner wall

Claims (2)

One to-be-fastened member in which the female thread portion is formed;
The other to-be-fastened member in which a recess having a through hole and a predetermined inner diameter continuous therewith is formed;
Between the male screw part screwed into the female screw part and the head, a bolt with a hole in which a neck part whose outer diameter gradually increases as it goes from the male screw part side to the head side,
An annular reverse rotation prevention ring having a predetermined outer diameter having a central hole through which a part of the neck of the bolt is inserted, and a slit leading to the central hole;
With
Both the fastened members are fastened by screwing and tightening the male threaded portion of the bolt to the female threaded portion through the recess and the through hole, and the reverse rotation prevention ring is pushed and widened by tightening, The outer wall is in contact with the inner wall of the recess ,
The said reverse rotation prevention ring has a narrow part in the opposing part of the said slit, The fastening structure characterized by the above-mentioned . One to-be-fastened member in which the female thread portion is formed;
The other to-be-fastened member in which a recess having a through hole and a predetermined inner diameter continuous therewith is formed;
Between the male screw part screwed into the female screw part and the head, a bolt with a hole in which a neck part whose outer diameter gradually increases as it goes from the male screw part side to the head side,
An annular reverse rotation prevention ring having a predetermined outer diameter having a central hole through which a part of the neck of the bolt is inserted, and a slit leading to the central hole;
With
Both the fastened members are fastened by screwing and tightening the male threaded portion of the bolt to the female threaded portion through the recess and the through hole, and the reverse rotation prevention ring is pushed and widened by tightening, The outer wall is in contact with the inner wall of the recess,
The fastening structure according to claim 1, wherein the half ring portions defined by the line passing through the center and the slit in the reverse rotation prevention ring have different radial widths .

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